Highly stressed turbine components, such as integrally bladed turbine rotors or blisks (bladed disks), are used in a wide variety of environments, such as in gaseous hydrogen, gaseous oxygen, and high concentration hydrogen peroxide systems. Often times, these components are manufactured by consolidating a powdered metal material, such as a conventional high-strength, nickel-based superalloy that is subsequently coated for environmental protection, or made from a moderate strength alloy that is fully compatible with the applicable environment.
However, conventional coatings can introduce reliability and cost issues while the moderate strength alloys potentially sacrifice some strength. Moreover, when hot isostatic pressing of a powdered metal material is employed to net shape the article, both of these alternatives suffered from surface micro-roughness and surface contamination by carbon diffusion when known hot isostatic pressing techniques had been employed. These problems were due to powder indentation and diffusion bonding with the soft tooling used during consolidation of the powdered metal and could result in reduced high cycle fatigue life.